5/5 here. The idea behind this story was just fantastic by itself. Add on the amazing acting and good writing, and you get this masterpiece. I think this is Donna's best episode by quite a stretch.
11 - Susan 11 - Ian 27 - Barbara 08 - Vicki 06 - Steven 09 - Sara 07 - Katarina 10 - Dodo 11 - Polly 10 - Ben 09 - Jamie 09 - Victoria 08 - Zoe 21 - Liz 24 - Jo 12 - The Brigadier 08 - Benton 12 - Sarah 06 - Harry 34 - Leela 15 - Romana I 10 - Romana II 08 - Nyssa 19 - Peri 36 - Ace 15 - Rose 09 - Jack 09 - Astrid 33 - Donna 05 - Adelaide 12 - Wilf 15 - Amy 11 - Rory 18 - River 11 - Clara
Normal Space, or N-Space for short, is a name given to the prime universe to distinguish it from the smaller E-Space. The majority of the Doctor's adventures happen in this universe.
07 - An Unearthly Child 14 - The Daleks 08 - The Edge of Destruction 15 - Marco Polo 12 - The Keys of Marinus 13 - The Aztecs 03 - The Sensorites 08 - The Reign of Terror